Investigators at the Harbor-UCLA Medical Center and the Miller Children's Hospital-Long Beach Memorial Medical Center propose to continue to participate as a combined unit in the scientific activities of the Childrens Cancer Group (CCG). The applicant is a leading CCG institution in entries onto therapeutic studies including first line, second line, and new agent studies. In addition, we are a leading institution in entries onto special studies including epidemiologic studies, pharmacology studies, and other studies either immunologic or supportive in nature. The applicant is supervising over 700 children in active follow-up. Our scientific priorities include CCG trials of treatment, procedures, and management strategies with the objective to place eligible patients on trials of new therapeutic agents. The applicant is one of a select group of CCG institutions approved to conduct limited institutional Phase I and Phase II studies. We have developed and are committed to continue to develop studies which will be the basis of CCG nationwide protocols. We are committed to continue to contribute to the following CCG activities: Wilms' Tumor Strategy Group, Pathology Committee, Supportive Care Committee, Psychology Committee, Therapeutic Committee Studies in Leukemia, Solid Tumors, and New Agents. The unit is also involved in research programs in cellular and molecular immunology which should serve as a basis for additional CCG studies. There is a strong psychosocial program dedicated to facilitate the restoration of health and normal childhood reintegration into the community. The program is organized in a multidisciplinary manner with pediatric oncologists, surgeons, radiotherapists, pathologists, immunologists, and geneticists committed to cooperate with CCG in the concept, design, conduct, analysis, and the reporting of clinical investigations of children with cancer. Pediatric hematologists and oncologists supervise the direct patient care and recording of data by a trained data managerial staff. Results are forwarded to the Childrens Cancer Group Operation's Office for compilation and statistical analysis.